WILSONVILLE, Ore.--Mentor Graphics Corp. here today announced its Calibre division has struck an R&D alliance with the IMEC research group in Europe to jointly pursue new resolution enhancement technology (RET) for subwavelength lithography used with 193- and 157-nm exposure tools.

Under a three-year agreement, IMEC will use Mentor's Calibre software in a collaborative effort to advance process capabilities in high-numerical aperture (NA) 193- and 157-nm lithography. IMEC in Leuven, Belgium, and Mentor said they have been informally collaborating since 1999.

One area of research planned by Mentor and IMEC will be in double-exposure dipole decomposition resolution enhancement techniques, which use less expensive binary masks but still achieve enhanced resolutions similar to alternating, strong phase-shift masking, according to officials. This approach is considered to be a leading candidate for sub-100-nm "strong" RET software, said Mentor and IMEC.

"Because Calibre makes use of all four resolution enhancement technologies, namely optical and process correction, phase-shift mask, scattering bars and off-axis illumination--including the very promising double-exposure dipole decomposition technique for the 70-nm node--our researchers have the tools they need to realize major breakthroughs," said Luc Van den hove, vice president of IMEC's silicon process technology division. "This is an important asset for the further developments within our 193-nm and 157-nm optical lithography IIAPs IMEC's industrial affiliation programs."

As part of the new agreement, Mentor will become a formal member of the industrial affiliation programs for development of high-NA 193-nm and 157-nm lithography and will continue to provide software, training and consulting.

Previously, Mentor and IMEC collaborated on testing the feasibility of gate patterning using 248-nm alternating phase shift masking (PSM) for sub-100-nm technology. The recent project used the Calibre software to create a phase-shift masked layout. As reported at the Photo Mask Japan conference in 2001, Calibre and IMEC were able to obtain functional isolated gates of 70 and 50-nm by using extra trimming techniques, said Mentor.